Apple Inc. has removed some virtual private network applications from its stores in China, a move that could block users ability to bypass a local web firewall and access overseas sites.

“We have been required to remove some VPN apps in China that do not meet the new regulations,” Carolyn Wu, Apple’s China spokeswoman told Bloomberg in an emailed response, referring to rules issued by the Ministry of Industry and Information Technology earlier this year that asks all developers offering VPNs to obtain a government license.

VPNs are popular in China as they help users get around the Great Firewall, a system used by China to control Internet access. The removal is the latest sign of China’s tightening measures to block individuals’ access to virtual private networks, following shutdowns of several popular VPN services. Policy makers have prioritized stability ahead of a twice-a-decade leadership reshuffle due in the fall.

Wu said the VPN apps remain available in all other markets where Apple does business.

China’s MIIT didn’t immediately respond to a Bloomberg’s fax seeking comment on the issue out of business hours.